With all these adjustments going up and down. What's up with Vgchartz? When I first got on this website, I assumed that these sales numbers were right on or really close to the actual sales. Recently, I saw Banjo-kazooie Nuts&Bolts, De Blob, HotD 2&3, and a lot of Nintendo's games get adjusted down massively. On the other hand, Call of Duty: World at War (Wii) , Boom Blox got adjusted up. I hope that all these games on this website are correct because its really getting annoying.

What do you guys think about this issue?  

Well, games get adjusted based on more information. I assume you would prefer more accurate information over less accurate information?
It's clear that we are quite accurate most of the time, but we don't have massive amounts of data, so when extra data comes in the statistics can be recalculated.

Right after the earnings reports of companies there's a lot of new info, hence adjustments.

VG Chartz is free, I have nothing to complain about. Now if I was paying to get these numbers, yeah they better be spot on!!! u_u

Here is something to consider.

VGChartz puts out weekly US numbers. Some stores actually report sales weekly, some bi-weekly, and some monthly. Because of this, sales get more accurate the longer you wait for results. Also, you have publishers who give out sales numbers on occasion.

Since VGChartz puts out a weekly number before receiving all the information for that week (people who report monthly won't report that week for up to another 3 weeks) the numbers are least likely to be accurate as soon as they come out. 1 week later more information is gathered and then combined with the old information. VGChartz could attain greater accuracy by just releasing numbers 1 time per month, but then it would lose its great feature of weekly numbers.

This is part of the reason why the prediction league doesn't pay out results until "updates" are allowed. For example, Stoked was supposed to come out a few weeks ago and got delayed. This screwed up the results, as VGChartz was getting preorder numbers in, and confused them for actual sales. 1 week goes by, and the sales were taken away.

Well apparently the Vgchartz team isn't all knowing and don't have the sales to EVERY single game spot on..

Of course they could pretend they're perfect and never adjust numbers when more data is provided..

It really depends on what you're looking for!

With estimates like these, it's less a matter of "How correct are they" as it is "How incorrect are they" in the sense that the numbers start out as incorrect and become less incorrect over time.

If you're looking for a solid and reliable number for sales, then good luck finding it. 

If you're looking for a reasonable estimate with a fair margin of error, then vgChartz works.

As the others have said there is a margin of error. Especially in software and especially in Others as it is harder for the team to get data for both of those.

As new data comes in they adjust the sales data accordingly.

I would like some notification of adjustments, but of course making figures more accurate is better than just leaving them

I'm here for the forums.

Hows about less moaning and more 'thanks a lot for doing this all for free vgc' yeah?